I'd also pull the plates and check the wear to the friction surfaces. Also, some guys will replace their plates before they get too bad. They're a bit like tyres. Some guys change them early, others wait till the canvas is showing. I personally like to get the most out of something while still performing safely.
One of my 748's is way more hammered than that with similar mileage. All I've ever done is take the plates out and dust/clean round the basket. Never slips, bangs and rattles beyond belief but works just fine so I leave it alone.
I generally swap the 'top' few friction plates, which tend to wear the most, with some from the bottom of the pack when the clutch starts to feel a bit tired. I take the view that the time to replace clutch components is when the clutch no longer operates properly. Decibels have no impact on this as far as I'm concerned. Others may take a different view.
